Pluralism
The United States is a society composed of many groups of people, some of whom originally belonged to other societies. Sociologists consider the United States a pluralistic society, meaning it is built of many groups. As societies modernize, they attract people from countries where there may be economic hardship, political unrest, or religious persecution. Since the industrialized countries of the West were the first to modernize, these countries tend to be more pluralistic than countries in other parts of the world.
Many people came to the United States between the mid-nineteenth and mid-twentieth centuries. Fleeing poverty and religious persecution, these immigrants arrived in waves from Europe and Asia and helped create the pluralism that makes the United States unique.